<?xml version="1.0"?><ownershipDocument><schemaVersion>X0201</schemaVersion>    <documentType>3/A</documentType><periodOfReport>2003-12-31</periodOfReport><dateOfOriginalSubmission>2004-01-07</dateOfOriginalSubmission><noSecuritiesOwned>0</noSecuritiesOwned><issuer><issuerCik>0000075129</issuerCik><issuerName>OTTER TAIL CORP</issuerName>        <issuerTradingSymbol>OTTR</issuerTradingSymbol></issuer><reportingOwner><reportingOwnerId><rptOwnerCik>0001274622</rptOwnerCik><rptOwnerName>BOHN KAREN</rptOwnerName></reportingOwnerId><reportingOwnerAddress><rptOwnerStreet1>215 S CASCADE ST</rptOwnerStreet1><rptOwnerStreet2></rptOwnerStreet2><rptOwnerCity>FERGUS FALLS</rptOwnerCity><rptOwnerState>MN</rptOwnerState><rptOwnerZipCode>56537-2801</rptOwnerZipCode><rptOwnerStateDescription></rptOwnerStateDescription></reportingOwnerAddress><reportingOwnerRelationship><isDirector>1</isDirector><isOfficer>0</isOfficer><isTenPercentOwner>0</isTenPercentOwner><isOther>0</isOther></reportingOwnerRelationship></reportingOwner><nonDerivativeTable><nonDerivativeHolding><securityTitle><value>Common Stock</value></securityTitle><postTransactionAmounts><sharesOwnedFollowingTransaction><value>0</value><footnoteId id="F1" /></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership></ownershipNature></nonDerivativeHolding></nonDerivativeTable><footnotes><footnote id="F1">Otter Tail Corporation's board of directors appointed Karen M Bohn to the Board of Directors, effective December 31, 2003.  As of this date, she has no Otter Tail Corporation securities to report.</footnote></footnotes><remarks></remarks><ownerSignature><signatureName>/s/ Karen M Bohn by Debra J Lill - POA</signatureName><signatureDate>2004-01-07</signatureDate></ownerSignature></ownershipDocument>

